Electric switch



DeC- 31 1929- A. B. HENDRlcKs, JR 1,741,296

ELECTRIC SWITCH Filed April 3, 1928 Fig). 5.

AI lan B. Hendricks, J r: wmf/81M H i s Attorney.

Patented Dec.l 31, 1929 UNITED STATES PATENT voI-"Fl'cr:

ALLAN IB. HENDRICKS, JR., F PITTSFIEL, MASSACHUSETTS, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION 0F NEW YORK i ELECTRIC SWITCH l Application led April 3,

My invention relates to electric switches. Considerable use has beenmade of switches of the type in which a plurality of fixed contact members surround a central shaft which '5 carries a movable contact making'-1nember.

The general object of the invention is to provide a switch of this type having an improved arrangement for operating the contact making member.

The invention will be better understood from the following description taken in connection with the accompanyingl drawing in which Fig.. 1 shows a face view of a switch constructed in accorda-nce with the invention, some of the hidden parts being indicated by broken lines, Fig. 2 is a sectional view on the line 2 2 of Fig. 1, Fig. 3 is a sectional view on the line 3-3 of Fig. 2 and Fig. 4 is a'view similar to Fig. 3 but with the movable parts of the switch in a different position.

Like reference characters indicate similar parts in different figures of the drawing'.

In the particular arrangement shown in the drawing, a face plate 10 and a back plate 11, formed of suitable insulating material, are secured in spaced relation by six fixed contact 'members or posts 12 to 17 inclusive,

the plates 10 and 11 being tightened against shoulders on the posts by screws 18 as shown in Fig. 2;

ing a handle 2O is mounted to turn in the plates 10 andll, the posts 12 to 17 being spaced uniformly about this shaft 19. A fbearing 21 for the shaft 19 is set into the plate 1() and between this' bearing and the shaft is interposed a sleeve 22, the purpose of which will be described later. The shaft 19 has an eccentric portion 23 surrounded by a sleeve 24 with two spaced projecting arms 25. A contact making member or connector 26 is secured by screws 27 to a rod 28 inserted through and rotatable in* openings in the outer ends of the arms 25.

Two spaced stops 29 on the sleeve 24 engage the projecting head of one of the screws 27 to limit the angular motion of the connector 26 relatively to the sleeve 24. The ends of the rod 28 project into grooves 30 in the. inner faces of the plates 10l and 11 to guide the A central rotatable shaft 19 hav- 1928. Serial No. 267,109.

connector 26 as it is moved between contact making positions by turningthe shaft 19.

The switch is operated bv turning the shaft 19 in the direction in which it is desired to move the connector 26. This connector 26 is shown in Figs. 1,- 2 and 3 in the position in which the contact surfaces at its opposite ends are pressed tightly against the fixedv contacts 12 and 13 so that it is making connection between thesetwo4 fixed contact-s.

Assume that it is desired to.move the connector 26 in a clockwise direction to its next contact making position where it will connect the two fixed contacts 13 and 14. This may be done .by turning lthe shaft 19 in a clockwise direction and, as will be seen later, through a complete revolution plus an angle equalv to that between the two consecutive contact making positions of the connector 26. Whenever the shaft 19 is rotated, the friction between its eccentric portion 23 and the sleeve 24 tends to cause rotation of the sleeve with the shaft. The connector 26 is' supported from the shaft 19 by the sleeve 24 with its arms 25 and the rod 28 so that whenever the sleeve 24 rotates about or with the shaft 19, the connectorv26 must rotate with it. Rotation of the shaft 19 with its eccentric vportion 23 causes they sleeve 24 to move so that its axis describes a. small circle about the axis of rotation of the shaft 19. As the shaft 19 starts to rotatefrom the position shown in Figs. 1, 2 and 3, the connector 26 cannot rotate with it because lthe connector is pressed against the fixed contacts 12 and 13 and also'because of the shape of the grooves 30'. Thus, 'at first, the `sleeve 24 is moved slightly sidewiseand away from the Xed contacts 12 and 13, the outer ends of the arms 25. turning `slightly on the rod 28 and the connector 26v remaining in its original position Further rotation of the shaft 19 moves the sleeve 24 further away from the fixed contacts 12 and 13 and draws the connector 26 away from these contacts, the ends of the rod 28 being now pressed against the outer edges positions of the rod 28 corresponding to successive contact making positions of the connector 26. The ends of the rod 28 now follow the guiding grooves 30 until the eccentric portion 23 of the shaft 19 is directly opposite the rod 28 and the connector 26 when the positions of these parts will be as shown in F ig. 4. The friction between the eccentric portion 23 of the shaft and the sleeve 24 novv causes the ends of the rod 28 to press against the inner edges of the grooves 30 and further rotation of the shaft 19 will force the sleeve 24 toward the fixed contacts 18 and 14, the

lends of the rod 28 following the grooves 30 until finally the connector is pressed tightly against these contacts 13 and 14 and connects them together. lt is obvious that the connector 26 may be moved in this manner and in either direction to connect any desired pair of adjacent fixed contacts.

'In some cases, particularly after the parts may have become somewhat worn, the friclse tion between the eccentric portion 23 of the shaft 19 and the sleeve 24 may not be. sufficient to be reliable. lFor this reason, it is considered desirable to provide a spring pressed ball 31 held in a hollow extension 32 on the sleeve 24. As shown in F ig. 2, the eccentric portion 23 of t-he shaft 19 has a depression 33 into which the ball 31 is pressed whenever the shaft 19 is in a position corresponding to a contact making osition of the contactor 26, This increased fgiiction assures that the rod 28 will start along the grooves 80 in the proper direction, after which no friction on the sleeve 24 will be necessary until the rod 28 and the connector 26 have reached the position shown in Fig. 4. Corresponding to this position of the parts, a second, depression 34 in the eccentric portion 23 of the shaft 19 is provided to receive the ball 31 and again provide increased friction to assure that the -rod 28 and the connector4 will continue to move in the proper direction with the shaft 19.

fn order to provide an easily visible indication of the position of the connector 26 at any time, the outer end of the sleeve 21 is provided with a pointer 35 movable over a suitable series of numerals 36 on the face of the switch. An arm 37 on the inner end of the sleeve 2l has a bifurcated outer end spanning the rod 28. rfhus, the arm 37 must always point toward the connector 26 and will control the position of the pointer 35 to indicate the position of the connector.

The invention has been explained by describing a particular form of the invention and its o eration but it will be apparent that various c langes may be made without departing from the scope of the invention as defined 1n the appended claims.

What f claim as new and vdesire to secure by Letters Patent of the United States is 1. A switch including' a shaft, a plurality of fixed contacts spaced about said shaft, a consaid shaft,'and a projection movable with said connector and in said groove to guide said connector between contact making positions.

3. A switch including a shaft having an eccentric portion, a plurality of fixed contacts spaced about said shaft, a connector for said contactsfa sleeve surrounding said eccentric portion ot' the shaft, means supporting said y connector from said sleeve, means provided with a groove convex toward said shaft, and a projection movable with said connector and in said groove to guide said connector between contact making positions.

4. A. switch including a shaft having an eccentric portion, a plurality of fixed contacts spaced about said shaft, a connector for said contacts, a sleeve surrounding said eccentric portion of the shaft, said Iconnector being pivotally supported from said sleeve, means provided with a `groove convex toward said shaft, and a projection movable with said connector and in said groove to guide said connector between contact making positions.

5. A switch including a shaft having an eccentric portion, a plurality of fixed contacts spaced about said shaft, a connector for said' contacts, a sleeve surrounding said eccentric portion of the shaft, said connector being pivotally supported from said sleeve, means for limiting the pivotal motion of said connector relatively to said sleeve, means provided with a groove convex toward said shaft, and a projection movablewith said connector and in said groove to guide said connector between contact making positions.

6. A switch including a face plate, an operating shaft extending through said face plate, a sleeve surrounding said shaft, switch position indicating means carried by the outer end of said sleeve, and means connecting the innerend of said sleeve with a movable part of said switch to control said indicating means.

7. A switch including a face plate, an operating shaft extending through said face plate, a sleeve surrounding said shaft, switch position indicating means carried by the outer end of said sleeve, and an arm carried by the inner end of said sleeve and engaging a movable part of said switch to control said indicating means.

In witness whereof l have hereunto set my hand this 30 day of March, 1928..

ALLAN B. HENDRICKS, Jn. 

